The present invention is generally related to short range wireless communication systems, and more specifically related to short range wireless communication systems utilizing inductive coupling.
It is often desirable to conduct communications between two self contained portions of a system, such as a military man portable radio and associated equipment used to load information (e.g., configuration parameters) into the radio. Typically, many types of military equipment (e.g., man portable radios) require military hardening (e.g., enhanced vibration, shock, environmental, electrical specifications) and watertight integrity (e.g., submersible equipment), thus warranting self contained portions.
Several disadvantages are associated with typical systems, which require that communications between the pieces of equipment be conducted via wired cables and electrical connectors, such as bayonet lock connectors and threaded connectors, for example. One disadvantage is that, in the field, carrying cables and/or connectors can place a burden on an operator. The cables/connectors are heavy and bulky, thus tiring the operator and slowing his reactions. Also, the size of the cables/connector can result in the operator becoming less covert.
Another disadvantage is that in the field, or during an operation in which little time is available, connecting and disconnecting the portions of the system can take too long, thus possibly jeopardizing the mission.
Another disadvantage is that these types of cables/connectors are subject to corrosion and interference with the operation of the connector (e.g., dirt in the threads) due to weather conditions and operational requirements, such as being submersed in water and/or mud, for example.
Many military situations require covert operations, including secure communications between portions of the system. Due to the covert nature of many military operations, the cables connecting the portions of the system must be shielded to prevent unauthorized disclosure of the information being transferred. An associated disadvantage is that shielded cables/connectors tend to be heavy, bulky, stiff, and difficult to quickly connect and disconnect.
Wireless systems have been explored. However, many wireless systems require that the structure (envelope) of the portions of the system be modified to facilitate communications. For example, a window may be put into a metallic envelope to support an infrared link. A associated disadvantage is that the envelope of the equipment is compromised.
Many wireless systems do not adequately address the requirement for secure communications. For example, optical wireless systems may be subject to unauthorized monitoring/access simply by being visually observed. Furthermore, typical wireless systems utilizing electromagnetic communications means transmit signals which are also easily subjected to unauthorized access.
An improved secure communications connection is desired.
In one embodiment, a secure wireless communication system comprises a first portion and a second portion. The first portion comprises a first inductor and the second portion comprises a second inductor. The first inductor comprises a first end and a second end. The second inductor comprises a third end and a fourth end. The first portion and the second portion define a gap therebetween. Wireless communication is achieved across the gap through mutual inductance between the first inductor and the second inductor by aligning the first end with the third end, and the second end the said fourth end.
In another embodiment, a method for providing secure wireless communications includes aligning the first portion of the communication system having the first inductor with the second portion of the communication system having the second inductor. When aligned, the first and second inductors form a dual-gap toroidal core. A wireless communication signal is conveyed across the gaps between the first and second portions via the first and second inductors.